Heat-treating mechanism for coil springs



May 18, 1954 M. J. NELSON ET AL HEAT-TREATING MECHANISM FOR COIL SPRINGSFiled July 5, 1951 J33 INVENTORS May 18, 1954 v M. J. NELSON ET ALHEAT-TREATING MECHANISM FOR con. SPRINGS Filed July 5, 1951 4Sheets-Sheet 2 INVENTORS flea 7 22M J/l/e sora May 18, 1954 M. JVNELSQNET AL HEAT-TREATING uscuguxsm FOR 0011. SPRINGS Filed July 5, 1951 4Sheets-Sheet 3 May 18, 1954 M. J. NEL$ON El AL 2,678,988

HEAT-TREATING MECHANISM FOR con. SPRINGS 4 Sheets-Sheet 4 Filed July 5,1951 Patented May 18, 1954 UNITED STATES TENT OFFICE HEAT-TREATINGMECHANISM FOR COIL SPRINGS Application July 5,1951, Serial No. 235,154

17. Claims. 1

The invention relates to a heater mechanism for heat treating coilsprings. The heater mechanism of this invention is particularlyadaptable for use with a coil. spring producing machine, suchasdisclosed-in application Serial No. 700,197, filed by William E.Wunderlich on September 30, 1946, now Patent No. 2,664,202 or" Ju1y'22,1952, for individually heat treating the coil springs as they are formedby the machine.

'lheprincipal object of this invention is to provide an improved heatermechanism for heat treating coil springs wherein the end turns of thecoil spring are securely clamped and electrically contacted for passingelectrical current therethrough. thereby eliminating arcingand-providing uniform heat treating throughout the length or" the coilspring, wherein electrical current is applied to the coil spring onlywhen the end turns thereof are securely clamped and electricallycontacted wherein the interval of time dur ing which electrical currentis applied maybe readily adjusted for obtaining the desired heattreatment of the-coil springs, wherein the application of electricalcurrent to and the clamping and electrically contacting of thecoilsprings are positively and mechanically synchronized forfoolproofoperation, wherein the heater mechanism may be readily adjusted foraccommodating coil springs having different lengths, diameters, wiregauge and the like, wherein the heater mechanisin may be readily appliedto coil spring producing machines for synchronous operation therewith,and wherein the heater mechanism is simple in construction, foolproof inoperation and inexpensive to manufacture.

Briefly, the heater mechanism of this invention includes two pairs ofclamping members, one pair clamping and electrically contacting one endturn.- of a coil spring and the other pair clamping electricallycontacting the other end of the coil spring; Each pair of clampingmembers-includes a normally stationary clamping member and a clampingmember movable toward and'away from the normally stationary clampingmember. A pair of cams, operated by a rotatable shaft, move the movableclamping members toward and away from the normally stationary clampingmembers for securely clamping and electrically contacting each coilspring applied thereto. Means are provided for applying electricalenergy to the clamping members electrically-to heat treat the springsclamped thereby. Control meansincluding switch means and cam meansoperated'by the rotatable shaft applies electrical energy to theclamping members and hence to the coil spring only when the coil springis securely clamped and electrically contacted by the clamping members.The control means is adjustable to regulate the time interval duringwhich electrical energy is applied to the clamped coil springs. Therotatable cam shaft may be driven in synchronisin with a coil springproducing ma chine for heat treating the coil springs as they arefabricated. The positions of the rotatable cam shaft and the variousclamping members and cams operated thereby may be adjusted toaccommodate coil springs of different lengths, diameters, wire gaugesand the like.

llurther objects of this invention reside in the details of constructionof the heater mechanism and in. the cooperative relationships betweencomponent parts thereof.

Other objects and advantages of this invention will become apparent tothose skilled in the art upon reference to the accompanyingspecification, claims and drawings, in which:

1 is a diagrammatic illustration of a coil spring producing machine ofthe type disclosed in the aforementioned William E. Wunderlichapplication with the heat treating mechanism of this invention appliedthereto;

Figs. 2 and 3 are perspective views of a coil spring which may be heattreated by the heat treating mechanism of this invention, Fig. 2illustrating the spring before heat treating and Fig. 3 illustrating thespring after heat treating;

Fig. 4 is a schematic wiring diagram of the means for applyingelectrical energy to the coil springs being heat treated and the controlmeans therefor;

Fig, 5 is a front elevational view partly in section of the'heattreating mechanism of this invention illustrating the clamping membersseparated for receiving a coil spring;

Fig. 6 is a front elevational view of the heat treating mechanismshowing a coil spring clamped by the clamping members for heat treatingthe coil spring;

Fig. '2 is a top plan view of the heat treating mechanism;

Fig. 8 is an end. elevational view of the heat treatingmechanism-looking from the left of Figs. 5 and '7;

Fig. 9 is a Vertical sectional View taken substantially along the line 99 of Fig. 7

Fig. 10 is a sectional view taken substantially along the line ll-l t ofFig. '7

Fig; 11 is a view illustrating the position of the left endof the coilspring, as illustrated in Figs.

defense 3 5 and 6, and it is clamped by the left-hand clamping members;

Fig. 12 is a view similar to Fig. 11 but i1lustrating the position of,and the manner in which, the right end of the coil spring, asillustrated in Figs. 5 and 6, is clamped;

Fig. 13 is an enlarged sectional view through a pair of clamping memberstaken substantially along the line i3-l 3 of Fig. 14

Fig. i l is an elevational view of the right-hand clamping member ofFig. 13 loolring from the left; and

Fig. 15 is an exploded perspective view illus trating the manner inwhich the portion of the clamping member utilized for clamping the coilspring is constructed.

Referring first to Figs. 2 and 3, a coil spring to be heat treated isgenerally designated at it. It includes a plurality of innerconvolutions or turns it and a pair of end turns H2. The end turns i2terminate in knots 13. The coil springmay be plain as illustrated or theend turns thereof may be crimped or offset if so desired. When the coilspring is originally fabricated the knots it are located out of line, asillustrated in I Fig. 2, so that when the coil spring is heat treatedthe knots line up, as illustrated in Fig. 3, the heat treating of thecoil spring causing a twisting within the coil spring.

Any suitable machine may be utilized for the purpose of fabricating thecoil spring in and for purposes of illustration in this application Fig.l discloses a coil sprin producing machine generally designated at 55which may be of the type disclosed in the aforementioned William E.Wunderlich application. The machine it includes a base or standard isand a coilin mechanism ii for coiling wire into the double ended coilspring Hi. When the coil spring ii] is thus formed it is grasped byfingers carried by radial arms iii of a transfer mechanism which isintermittently rotated in a counterclockwise direction, as illustratedin Fig. 1. The coil springs id thus formed and grasped by the fingers id are advanced to a knotting mechanism wherein one end of the coilspring I5 is knotted as at I 3 and, if desired, crimped into an offset.The coil springs it are then advanced to a second knottin mechanism 22wherein the other end of the coil spring is knotted and may also becrimped into an offset if so desired. The knotted coil springs iii arethen advanced by the transfer mechanism to the heat treating mechanismof this invention, generally designated at 23. After the coil springsiii are heat treated they are advanced by the transfer mechanism to astacked mechanism 23 wherein the heat treated coil springs are stackedin nested form. Since the coil spring producing machine,diagrammatically illustrated in Fig. 1, is fully disclosed in the aforementioned William E. Wunderlich application, a further descriptionthereof is not considered necessary. The heat treating mechanism 23 ofthis invention includes a supporting base 26 in the form of an anglemember which is secured to the standard or support it of the coil springproducing machine by means of bolts 21. The upwardly extending leg ofthe supporting base 28 is provided with a plurality of holes 28 and isprovided adjacent each end with vertically ar-- ranged slots 29. A pairof bearing blocks 30 are secured to the supporting base by screws 31extending through the slots 29 and nuts 32. A rotatable cam shaft 33 isrotatably journalled by bearings 34 in the bearin blocks 30. By reason 4of the vertical slots 29 the bearing blocks 39 and, hence, the cam shaft33 may be vertically adjustably positioned as desired.

The right-hand end of the rotatable cam shaft 33, as viewed in Figs. 5and '7, has a hub 35 keyed thereto by a key 353 along with a set screw3! for holding the hub in proper position on the cam shaft. A gear at issecured to the hub 55 by means of bolts 39 so that as the gear 38 isdriven, the cam shaft 32 is correspondingly rotated. As shown in Fig. l,the gear 38 meshes with a driving gear 43 carried by a shaft 4! whichdrives the lrnotting mechanism 22. The shaft ll makes one completerevolution in its operation of the lmotting mechanism 22 and'this isdone during each cycle of operation of the coil spring producingmachine. The gear 33 is preferably twice the size of the driving gear asso that during each cycle of operation of the coil spring producingmachine the rotatable cam shaft 33 is driven through one-half arevolution.

The rotatable cam shaft slidably carries a pair of sleeves of identicalconstruction, the sleeves d5 being k yed to the shaft 33 for rotationtherewith by lreys ii. Each sleeve 35 rotatably and slidably carries apair of clamping members, a normally stationary clamping member 47 and amovable clamping member t3 which is movable toward and away from thenormally stationary clamping member 4?. Since the sleeves and theclamping members and elements associated with each sleeve are identicalin construction, like reference characters have been utilized for likeparts.

The normally stationary clamping member 4'! is journalled for rotationwith respect to the sleeve 45 by a bearing 49 and, likewise, the movableclamping member as is journalled for rotation on the sleeve :5 by abearing member 50. The normally stationary clamping member 41 abutsagainst a thrust bearing 5| which is positioned on the sleeve 55 by ascrew-threaded collar 52, which in turn is locked in adjusted positionby a locking collar 53. The collars 52 and 53 may be adjustablypositioned on the screwthreaded portion of the sleeve 45 by means of asuitable tool extending into radial openings 54 in the collars 52 and53. Thus the collar 52 determines the relative lengthwise positions ofthe normally stationary clamping member 41 and the sleeve 45. A spring55 is interposed between the normally stationary clamping member ill andthe movable clamping member 33 for normally separating these members.

A cam member 5% is secured to the movable clamping member 48 by means ofscrews 5'! and this cam member $56 is provided with a pair ofdiametrically opposed and longitudinally extending cam surfaces 58. Acam 58 is slidably carried by the sleeve "55 and abuts against a ringsecured in an annular groove in the sleeve 45, the ring 69 limitinginward movement of the cam 59. The cam 59 is keyed to the sleeve 45 by akey 6! so that the cam 69 rotates with the sleeve 45 and, hence, withthe shaft 33, although the cam 59 may move longitudinally on the sleeve45. The cam 59 is also provided with a pair of diametrically opposedlongitudinally extending cam surfaces 52 which cooperate with the camsurface 58 on the cam member 56. The cam 59 is normally maintainedagainst the ring 68 by means of a spring 63, one end of which abuts thecam 59 and the other end of which abuts a collar 64 screw-threaded onthe sleeve 45. The collar 64 is locked in adjusted position on thesleeve 45 by" means of a'screw-threaded lock collar 65,radial-'openingslifi in the collars 84 and 65 facilitating' theiradjustment.

When the cam surfaces 58 and 62 are not in engagement, as illustrated inFig. '7, the springs 59 separate the clamping members d? and 48, asillustrated in Figs. 5 and '7. However, when the cam shaft 33 and,hence,-the sleeve it rotate to a position wherein'the cam surfaces 58and E52 engage each other, as illustrated in Fig. 6,the movable clampingmembers 48 are moved toward the normally stationary clamping members Allfor the purpose of clamping the end turns of a coil spring Illtherebetween. In the event that movement of the movable clamping member48 toward the clamping member d? is impeded, as, for example, a knot l3inadvertently being interposed therebetween, the cam 59 backs away fromthe ring 6% against the action of the spring t3. Accordingly, the springacts as a strain release for the cam 59 to prevent breakage of the partsunder these conditions.

As illustrated in more detail in Figs. 5 and 13 to 15, the upper ends ofeach clamping member 41 and A8 are provided with transverse recesses 68and the extending portions of the clamping membersare provided withholes 69. The recesses 68 each receive an angular electrical insulatingmember 10 which is also provided with holes ii and a flared extension12. In turn, each angular electrical insulating member it! carries anelectrode 13 having tapped holes "M and a flared extension 15. Bolts 8G,electrically insulated by suitable electrical insulating sleeves 8iextend through the'holes 69 and H into the tapped holes 14 in theelectrode F3 for securing the electrode 13 to, the clamping member 4'!and at the same time electrically insulating the same from the clampingmember. One of the electrodes "it, as illustrated in Fig. 5, or more ofthe electrodes if so desired, may be recessed at it for receiving anangular insulating member 1 and an angular metallic wear plate '59,which in turn are provided with holes '53 for receiving the screws forholding the same in place. These angular electrically insulating membersIf and wear plates 19 overlie the electrodes '13 in order to prevent aninner convolution I of the coil spring it from contacting theelectrodes, as illustrated in Figs.

5 and'll. This prevents any arcing at this point which would weaken thecoil spring and which would also interfere with the proper heattreatment of the same. Since, in the operation of this particular formof the heat treating mechanism, the inner convolutions of the coilsprings might engage the electrodes 13 at only one point, as illustratedin Figs. 5, 11 and 12, only one of the electrodes i3 is provided withthe overlying electrical insulating member. Of course, if desired, theother electrode 13 may also be provided with this feature.

The flared ends '15 of the electrodes 73 are for the purpose offacilitating the insertion of the end turns of the coil springs betweenthe two pairsof clamping members 4'? and 48. Electrical connection ismade to the opposite extending ehds'of the electrodes l3. Here aflexible electrical conducting strip-83 is secured to the ends of theelectrodes T3 of each pair of clamping members by means of screws 84entering tapped holes 85- in the electrodes. Thus the electrodes of eachpair of clamping members are electrically connected together andelectrical energy may be suitably applied thereto by suitable connectors86 held in place by the screws 84.

The two pairs of clamping members 41. and :48. extend downwardly belowthe rotatable cam shaft 33, the normally stationary clamping members 47being wider than the movable clamping members Q8. The normallystationary clamping members 41' are normally clamped between the.upwardly extending leg of the supporting base 2-6 and a bar 88, thisbeing accomplished by a bolt 89 extending through one of the holes 28 inthe supporting base and a hole in the bar 88 along with a nut 99. Thus.the bar 88, in addition to clamping the normally stationary clampingmembers if in desired positions, also operates to prevent rotation ofthe clamping members 41 as the cam shaft 33 and, hence, the sleeye 45are rotated. The movable clamping members 38 being narrower than thenormally stationary clamping members 47 are not clamped torthesupporting base 26 so that these clamping :members 43 may be movedtoward and away from the normally stationary clamping members 41.However, the bar 88, cooperating with the supporting base 26, does holdthe movable clamping members 38 against rotation as the cam shaft 33and, hence, the sleeve 45 are rotated. By loosening the bolt iia thestationary clamping members 4'! may be adjusted to desired positionsalong the cam shaft 33 for accommodating any desired length of coilspring H]. When the normally stationary clamping members 47 are thusmoved to the desired positions, the. sleeves 45 and the other partscarried thereby are correspondingly moved. When the desired adjustmentis obtained, then the bolt 89 is tightenedto maintain this desiredrelationship. The plurality of holes 23 in the supporting base-25 permitpositioning of the clamping members substantially anywhere along the camshaft 33. To accommodate coil springs of different diameters the camshaft 33 and, hence, the clamping members carried thereby may bevertically raised or lowered by manipulation'of the bearing blocks 39.To adjust the pressure at which the clamping members ll and d3 clamp theend turns of the 5 coil springs, all that is necessary is to adjust thepositions of the collars 52 and 53. The adjustment should be such thatthe electrodes 13 bite firmly the end turns 12 of the coil springs.

The cam shaft 33 adjustably carries for rotation therewith a cam havinga pair of diametrically opposed cam surfaces 91, the cam 95 beingsecured to the cam shaft by a set screw 95. A conventional normally openelectric switch 98 is secured underneath the cam 95 to the adjacentbearing block it by means of screws 9|. This normally open switch $8 isprovided with a plunger act in turn carrying a cam follower illl whichis operated by the cam surfacess'i on the cam 95. Thus, when the camshaft 33 and, hence, the cam 95 are rotated, the cam surface 81 engagesthe cam follower ltd momentarily to close the switch 98. The cam 95 isso positioned on the cam shaft 33 that the switch 98 is momentarilyclosed only after the clamping members 6? and 43 have securely clampedthe nd turns 12 of the coil spring to be heat treated. The switch 98 isprovided with a suitable conduitconnector N12 for accommodating the leadwires thereof.

The end of the cam shaft 33 also carries another cam I05 having a pairof diametrically opposed cam surfaces Hit, the cam being .adjusta-blysecured to the cam shaft 33 by a set screw, not shown. Rotatably mountedon the cam shaft 33 between the cam Hi5 and the bearing block 30 is aswitch supporting plate III'I having a lower outwardly extending portionI38 which carries a normally closed electric switch I09. The switch itsis provided with a plunger III) which in turn carries a cam follower IIIto be engaged by the cam surfaces 33 as the cam shaft 33 is rotated.When a cam surface I33 engages the cam follower III the switch I39 ismomentarily opened. The switch I09 is also provided with a suitableconduit connector II2 for accommodating the switch leads. The switchsupporting plate It! is also provided with an upper outwardly extendingportion its to which is secured a handle H3. By moving the handle H5 theplate iill and the switch I03 are correspondingly moved about the axisof the cam shaft 33 so that the switch I39 may be momentarily opened atvarious points in the rotation of the cam shaft 33, depending upon theadjustment of the switch carrying plate I37. Thus, the time at which theswitch I33 is momentarily opened with respect to the time at which theswitch 93 is momentarily closed may be adjusted at will by manipulationof the handle H5. The switch carrying plate it? is provided with anarcuate slot II6 which is concentric with the axis of rotation of thecam shaft 33.

overlying the switch carrying plate It! is a plate II8 having a lowerinwardly extending portion I i 3 which is secured to the bearing block33 by screws 23. The upper end of this plate H8 is provided with indiciaIfii cooperating with a suitable marker on the upwardly extendingportion IIfil of the switch carrying plate iii! to indicate the intervalof time between the closing of the normally opened switch 33 and theopening of the normally closed switch The top of the bearing block 30has a bracket I22 secured thereto by screws I23 and a screw its isstaked thereto. This screw 524 extends through the arcuate slot H3 andthrough a hole in the outer plate H3. A. wing nut E25 carried :by thescrew I24 clamps the switch carrying plate Iil'I in adjusted positionbetween the bracket I22 and the plate II8.

Electrical energy is applied to the clamping members 31 and 43 and,hence, to the coil spring clamped thereby by means of a low voltage highcurrent transformer which is designated generally at 533 in Fig. 4. Thistransformer is of conventional construction and has a primary I3I and asecondary i322, the secondary I32 being connected by suitable leads I33to the connectors 33 carried by the electrodes 73. Electrical energy issupplied to the primary of the transformer means of conductors I33 andI35 leading from some source of power not shown. The application ofelectrical energy to the primary i3I of the transformer 533 iscontrolled by a relay having an operating coil 533 for operatingswitches I3'i, I33 and iii When the relay coil E33 is energized theswitches I31, I33 and E33 are closed and when the relay coil I36 isdeenergized these switches are opened. The switches I3! and A33 controlthe application of electrical energy to the transformer primary i3i sothat when the relay is energized, electrical energy is applied to thetransformer and when it is deenergized the application of electricalenergy is interrupted. The switch I33 of the relay operates to completea maintaining circuit for the relay.

The relay winding I 33 is controlled by the normally opened switch 93and the normally closed switch Hi3 operated by the cam shaft 33.

Fill

It may also be controlled by a switch MI and a. start and stop switchI42. The switches I II, I42, 139 and 98 are connected in series with therelay coil 36 and the relay switch I39 is connected in shunt with thenormally opened switch 93. In order to energize the relay coil I33 theswitches MI, I42, I09 and 98 must be closed and the relay may bemaintained energized through the switches I II, I42, I03 and I39independently of the switch 98 until switch I09 or switches I4! and I42are opened.

Assuming that the switches MI and I42 are closed and that the coilspring producing machine is in operation with a coil spring to be heattreated moved between the clamping members 47 and 48 and securelyclamped therebetween, the normally opened switch 98 is thereafter closedto complete a circuit from the conductor I through switches I Il, I42,I39, 98 and relay coil I33 to the conductor I 34. This energizes therelay coil I33 for closing the switches I31, I38 and E39. Closure of theswitches I31 and I38 applies electrical energy to the transformer I30and, hence, causes electrical current to course the coil spring II) forheat treating the same. Closure of the switch i539 upon energization ofthe relay coil I36 completes a maintaining circuit for the relay coilI36 independent of the switch 33 so that when the switch 98 opens therelay coil remains energized. Upon further rotation of the ca .1 shaft33 the normally closed switch its is opened at a point in the cycledepending upon the adjustment of that switch with respect to the camshaft 33. Upon opening of this switch I09 the maintaining circuit to therelay coil I33 is broken and the relay becom tie-energized for openingthe switches I31, and Opening the switches I31 and I38 interrupts theapplication of electrical energy to the coil spring i0 being heattreated. Opening of the switch I35 of the relay prevents the relay fromagain being energized until such time as the normally opened switch 93is closed during the next cycle of operation. Thus electrical energy isapplied to each coil spring clamped between the clamping members 4'! andS8 and the interval of time at which the electrical energy is so appliedis dependent upon the adjustment of the normally closed switch I09. Inall instances electrical energy is applied to the electrodes 13 onlywhen the end turns of the coil spring I2 are securely clamped by theclamping members 4'! and 48. By adjusting the normally closed switch:139 the amount of heat treatment appliled to each coil spring may beregulated at w1 An indicating lamp I44 may be connected across theconductors I34 and I35 to indicate that the heat treating mechanism isin condition for operation and an indicating lamp I may be connectedacross the primary I3! of the transformer I33 for indicating the periodof application of electrical energy to the coil spring being heattreated.

The switch ii in series with the relay coil I36 is operated by theclutch mechanism of the coil spring producing machine I5 so that therelay may be energized and electrical energy applied to the electrodesof the clamping members only when the coil spring producing machine isin operation. This effectively automatically prevents application ofelectrical energy to a coil spring when the coil spring producingmachine is shut down. The start and stop switch I42 is convenientlylocated on the coil spring pro- 9. ducing machine l 5 so that theapplication of electrical energy through the electrodes of the heattreating mechanism may be interrupted at the will of the machineoperator.

While for purposes of illustration one form of this invention beendisclosed, other forms thereof may become apparent to those skilled inthe art upon reference to this disclosure and, therefore, this inventionis to be limited only by the scope or" the appended claims.

We claim as our invention:

1. A lieate' mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the base, a first pair ofclamping members fixedly mounted at one position along the shaft forclamping and electrically contacting one end turn of a coil spring andincluding a normally stationary clamping member and a clamping membermovable toward and away from -,;1e normally stationary clamping member,a second pair of clamping members fixedly mounted at another positionalong the shaft for clamping and electrically contasting the other endturn of the coil spring and including a normally stationary clampingmember and a clamping member movable toward and away from the normallystationary clamping member, and a pair of cam means carried and rotatedby the shaft for engaging and. moving the movable clamping members ofthe two pairs of clamping members.

2. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the base, a pair ofclamping members fixedly mounted at one position along the shaft forclamping and electrically contacting one end turn of a coil spring andincluding normally stationary clamping mem ber and a clamping membermovable toward and away from the normally stationary clamping member, asecond pair of clamping members fixedly mounted at another positionalong the shaft for clamping and electrically contacting the other endturn of the coil spring and including a normally stationary clampingmember and a member movable toward and away from the normally stationaryclamping member, a pair of cam means carried and rotated by the shaftengaging and moving the movable clamping members of the two pairs ofclamping for applying electrical energy to two pairs of clamping memberselectrical-- ly to heat the coil spring clamped thereby, control meansfor controlling said last men tioned 5 including switch and cam meansca: led rotated by the shaft for oper ating the itch means to applyelectrical energy to the two pairs or" clamping members only when thecoil spring is clamped thereby.

3. A heater mechanism for heat treating coil springs comprising, asupporting base, a rotatably mounted on the base, a first pair orclamping members fixedly mounted at one position along the ior clampingand electrically contacting one end turn of a coil spring including anormally stationary clamping mema clamping member movable toward and thenormally stationary clamping a second pair of clamping members :lly in.nnted at another position along the "t for clamping and electricallycontacting the other end turn of the coil spring and inclutb normallystationary clamping member a clamping member movable toward and awayfrom the normally-stationary clam-ping member,

10 a pair of cam means carried andoperated by the shaft for engagingand. moving the movable clamping members of the two pairs of clampingmembers, means for applying electrical energy to the two pairs ofclamping members electrically to heat treat the coil spring clampedthereby, and control means for controlling said last mentioned meansincluding switch means and means carried and rotated by the shaft foroperating the switch means to apply electrical energy to the two pairsof clamping members only when the coil spring is clamped thereby, saidcontrol means being adjustable to regulate the time in- "erval duringwhich electrical energy is applied to the two pairs of clamping members.

A heater mechanism for heat treating coil s1. .ings comprising, asupporting base, a shaft rotatably mounted on the base, a first pair ofclamping members fixedly mounted at one position along the shaft forclamping and electrically contacting one end turn of a coil spring andincluding a normally stationary clamping member and a clamping membermovable toward and away from the normally stationary clamping member, asecond pair of clamping members fixedly mounted-at another positionalong the shaft for clamping and electrically contacting the other endturn of the coil spring and including a normally stationary clampingmember and a clamping member movabletoward and away from the normallystationary clamping member, a pair of cam means carried and operated bythe shaft for engaging and moving the movable clamping members of thetwo pairs of clamping members, means for applying electrical energy tothe two pairs of clamping members electrical ly to heat treat the coilspring clamped thereby, and control means for controlling said lastmentioned means including a relay, a first cam operated switchoperated-bythe shaft for energizing the relay and a second cam operatedswitch operated by the shaft for deenergizing the relay to applyelectrical energy to the two pairs of clamping members only when thecoil spring is clamped thereby, one of said cam operated switches beingadjustable to regulate the time interval during which the relay isenergized and electrical energy is applied to the two pairs of clampingmembers.

5. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the base, a first pair ofclamping members fixedly mounted at one position along the shaft havingfacing insulated electrodes for clamping and electrically contacting oneend turn of a coil spring and including a normally stationary clampingmember and a clamping member movable toward and away from the normallystationary clamping member, a second pair of clamping members fixedlymounted at another position along the shaft having facing insulatedelectrodes for clamping and electrically contacting the other end turnof the coil spring and including a normally stationary clamping memberand a clamping member movable toward and away from the normallystationary clamping member, and a pair of cam means carried and rotatedby the shaft for en" gaging and moving the movable clamping members ofthe two pairs of clamping members.

6. A heater mechanism for heat treating coil comprising, a supportingbase, a shaft rotatably mounted on the base, a first pair of clampingmembers fixedly mounted at one position along t e shaft having facinginsulated elecll trodes for clamping and electrically contacting one endturn of a coil spring and including a normally-stationary clampingmember and a clamping member movable toward and away from the normallystationary clamping member, a second pair of clamping members fixedlymounted at another position along the shaft having facing insulatedelectrodes for clamping and electrically contacting the other end turnof the coil spring and including a normally stationary clamping memberand a clamping member movable toward and away from the normallystationary clamping member, a pair of cam means carried and operated bythe shaft for engaging and moving the movable clamping members of thetwo pairs of clamping members, and insulating means overlying the edgesof at least one of the electrodes of the clamping members to preventintermediate turns of the coil. spring from electrically contacting theelectrodes.

7. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on. the supporting base, afirst pair of clamping members fixedly mounted at one position along theshaft for clamping and e1ectrically contacting one end turn of a coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, a second pair ofclamping members fixedly mounted at another position along the shaft forclamping and electrically contacting the other end turn of the coilspring and including a normally stationary clamping member carried bythe shaft and. a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, means for holdingall of the clamping members against rotation with the shaft, and a pairof cams carried by the shaft and rotatable therewith and engaging themovable clamping members of the two pairs of clamping members for movingthe same with respect to the normally stationary clamping members.

8. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, afirst pair of clamping members at one position along the shaft for claring and electrically contacting one end turn of a coil spring andincluding a normally stationary clamping member carried by the shaft anda clamping member carried by the shaft and. movable toward and away fromthe normally stationary clamping member, a second pair of clampingmembers at another position along the shaft for clamping andelectrically contacting the other end turn of the coil spring andincluding a normally stationary clamping member carried by the shaft anda clamping member oarri :l by the shaft and movable toward and away fromthe normally stationary clamping member, means for bold" ing all of theclamping members against rotation with the shaft, springs interposedbetween the normally stationary and movable clamping members of eachpair of clamping members for normally separating the pair of camscarried by the shaft rotatable therewith and engaging the movableclamping members of the two pairs of clamping members for moving thesame toward the normally stationary clamp ing members against the actionof the springs.

9. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, afirst pair of clamping members fixedly mounted at one position along theshaft for clamping and electrically contacting one end turn of a coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and mov able towardand away from the normally stationary clamping member, a second pair ofclamping members fixedly mounted at another position along the shaft forclamping and electrically contacting the other end turn of the coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, means foradjustably positioning the normally stationary clamping members of thetwo pairs of clamping members along the shaft and holding the sameagainst rotation. with the shaft, means for holding the movable clampingmembers of the two pairs of clamping members against rotation with theshaft, and a pair of cams carried by the shaft and rotatable therewithand engaging the movable clamping members of the two pairs of clampingmembers for moving the same with respect to the normally stationaryclamping members.

10. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, afirst pair of clamping members fixedly mounted at one position along theshaft for clamping and electrically contacting one end turn of a coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, a second pair ofclamping members fixedly mounted at another position along the shaft forclamping and electrically contacting the other end turn of the coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, means foradjustably positioning the normally stationary clamping members of thetwo pairs of clamping members along the shaft and holding the sameagainst rotation with the shaft, means for holding the movable clampingmembers of the two pairs of clampin members against rotation with theshaft, springs interposed between the normally stationary and movableclamping members of each pair of clamping members for normallyseparating the same, and a pair of cams carried by the shaft androtatable therewith and engaging the movable clamping members of the twopairs of clamping members for moving the same toward the normallystationary clamping members against the action of the springs.

11. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft ro tatably mounted on the supporting base, afirst pair of clamping members fixedly mounted at one position along theshaft for clamping and electrically contacting one end turn of a coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and morable towardand away from the normally stationary clamping member, a second pair ofclamping members fixedly mounted at another position along the shaft forclamping and electrically con- 13 tactin'g ithe other 'end' turn of thecoil spring and including a normally stationary clamping member carriedbythe shaft and a clamping member carried by the shaft and movabletoward and away from the normally stationary clamping member, means foradjustably positioning the shaft with respect to the supporting base,'means for adjustably' positioning the clamping members of the two pairsof clamping memhere along the shaft and for holding the same againstrotation with'the shaft, and a :pair of cams carried by the shaft androtatable therewith and adjustable therealong and engaging the movableclamping members of the two pairs of clamping members for moving thesame'with respect to the normally stationary clamping members.

12. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, afirst pair of clamping members fixedly mounted at one position along theshaft for clamping and electrically contacting one end turn of a coilspring and includinga normally stationary clamping member carried by theshaft and a clamping member carr'ied'by the shaft and movable toward andawayfrom the normally stationary clamping member, a second pair ofclamping members fixedly mounted at another position along the shaft forclamping and electrically contacting the other end turn of the coilspring and including a normally stationary clamping member carried, bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, means for holdingall of the clamping members against rotation with the shaft, springsinterposed between the normally stationary and movable clamping membersof each pair of clamping members for normally separating the same, apair of cams carried by the shaft and rotatable therewith. and engagingthe movable clamping members of the two pairs of clamping members formoving the same toward the normally stationary clamping members againstthe action of the springs, and means including spring means forpermitting movement of cams away from their respective normallystationary clamping members in the event that movement of the movableclamping members toward their respective normally stationary clampingmembers is impeded.

13. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, apair of sleeves slidable on the shaft and keyed to the shaft forrotation therewith, a first pair of clamping members for clamping andelectrically contacting one end. turn of a coil spring i cluding anormally stationary clamping member rotatably and slidably carried byone of the sleeves and a clamping member rotatably and slidably carriedby said sleeve and movable toward and away from the normally stationaryclamping member, a second pair of clamping members for clamping andelectrically contacting the other end turn of the coil spring andineluding a normally stationary clamping member rotatably and slidablycarried by the other sleeve and a clamping member rotatably andslidablycarried. by said last mentioned sleeve movable toward and away from thenormally stationa-ry clamping member, a-collar adj secured to eachsleeve for limiting lengtwie movement of the normally stationaryclamping members carried thereby, springs located between the normallystationary and the movable clamping members of the two pairs of clampingmembers for normally separating the same, a cam slidably carried by eachsleeve keyed thereto for rotation therewith for engaging the movableclamping members to move the same toward the normally stationaryclamping members against the action of the springs, a second collaradjustably secured to each sleeve, a spring located between each saidsecond collar and its associatedcam for permitting movement of the camsaway from their respective normally stationary clamping lembers on theevent that movement of the movable clamping members toward theirrespective normally stationary clamping members is impeded, means foradjustably positioning the sleeves and the elements carried therebyalong the shaft and for securing the normally stationary clampingmembers in adjusted position to the supporting base and for holding thenormally stationary clamping members against rotation with the shaft andsleeves, and means for holding the movable clamping members againstrotation with the shaft and sleeves.

14. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, afirst pair of clamping members fixedly mounted at one position along theshaft for clamping and electrically contacting one end turn of a coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, a second pair ofclamping members fixedly mounted at another position along the shaft forclamping and electrically contacting the other end turn of the coilspring and including a normally stationary clamping member carried bythe shaft and a clamping member carried by the shaft and movable towardand away from the normally stationary clamping member, means for holdingall of the clamping members against rotation with the shaft, a pair ofcams carried by the shaft and rotatable therewith and engaging themovable clamping members of the two pairs of clamping members for movingthe same with respect to the normally stationary clamping members, meansfor applying electrical energy to the two pa'rs of clamping memberselectrically to heat treat the coil spring clamped thereby, and controlmeans for controlling said last mentioned means including switch meansand cam means carried and ro tated by the shaft for operating the switchto apply electrical energy to the two pairs of clamping members onlywhen the coil spring is clamped thereby.

15. A heater mechanism for heat treating coil springs comprising, asupporting a ro'tata'bly mounted on the supporting base, a first pair ofclamping members fixedly mounted at one position along the shaft forclamping and electrically contacting one end turn of a coil spring andincluding a normally stationary clamping member carried by the shaft anda clamping member carried by the shaft and mow able toward and away fromthe normally tionary clamping member, a cond p of clamping membersfixedly mounted at another position along the shaft for clampingelectrically contacting the other end turn of the coil spring andincluding a normally stationary clamping member carried by the shaft anda clamping member carried by the shaft and movable toward and away fromthe normally tionary clamping member, means for ho ol g all of theclamping members against rotation with the shaft, a pair of cams carriedby the t and rotatable therewith and engaging the movable clampingmembers of the two pairs of clamping members for moving the same withrespect to the normally stationary clamping members, means including arelay, a first cam operated switch operated by the shaft for energizingthe r and a second cam operated switch. operated by the shaft fordeenergizing the relay to apply electrical energy to the two pairs ofclamping members only when the coil spring is clamped thereby, one ofsaid cam operated switches being adjustable to regulate the timeinterval c which the relay is energized and electrical ergy is appliedto the two pairs of clan 1pm: members.

16. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, apair of sleeves slidable on the shaft and keyed to the shaft forrotation therewith, a first pair of clamping members for clamping andelectrically contacting one end turn of a coil spring and includ ing anormally stationary clamping member rotatably and slidably carried byone of the sleeves and a clamping member rotatably and slidably carriedby said sleeve and movable toward and away from the normally stationaryclamping member, a second pair of clamping members for clamping andelectrically contacting the other end turn of the coil spring andincluding a normally stationary clamping member rotatably and slidablycarried by the other sleeve and a clamping member rotatably and slidablycarried by said last mentioned sleeve and movable toward and away fromthe normally stationary clamping member, a collar adjustably secured toeach sleeve for limiting lengthwise movement or" the normally stationaryclamping members carried thereby, springs located between the normallystationary and the movable clamping members of the two pairs of clampingmembers for normally separating the same, a cam slidably carried by eachsleeve and keyed thereto for rotation therewith for engaging the movableclamping members to move the same toward the normally stationaryclamping members against the action of the springs, a second collaradjustably secured to each sleeve, a spring located between each saidsecond collar and its associated cam for permitting movement of the camsaway from their respective normally stationary clamping members I in theevent that movement of the movable clamping members toward theirrespective normally stationary clamping members is impeded, means foradjustably positioning the sleeves and the elements carried therebyalong the shaft and for securing the normally stationary clampingmembers in adjusted position to the supporting base and for holding thenormally stationary clamping members against rotation with the shaft andsleeves, means for holding the movable clamping members against rotationwith the shaft and sleeves, means for applying electrical energy to thetwo pairs of clamping members electrically to heat treat the coil springclamped thereby, and control means for controlling said last mentionedmeans including switch means and cam means carried and operated by theshaft for operating the switch means to apply electrical energy to thetwo pairs of clamping members only when the coil spring is clampedthereby.

1'3. A heater mechanism for heat treating coil springs comprising, asupporting base, a shaft rotatably mounted on the supporting base, apair of sleeves slidable on the shaft and keyed to the shaft forrotation therewith, a first pair of clamping members for clamping andelectrically contacting one end turn of a coil spring and including anormally stationary clamping member rotatably and slidably carried byone of the sleeves and a clamping member rotatably and siiclably carriedby said sleeve and movable toward and away from the normally stationaryclamping member, a second pair of clamping members for clamping andelectrically contacting the other end turn of the coil spring andincluding a normally stationary clamping member rotatably and slidablycarried by the other sleeve and a clamping member rotatably and slidablycarried by said last mentioned sleeve and movable toward and away fromthe normally stationary clamping member, a collar adjustably secured toeach sleeve for limiting lengthwise movement of the normally stationaryclamping members carried thereby, springs located between the normallystationary and the movable clamping members of the two pairs of clampingmembers for normally separating the same, a cam slidably carried by eachsleeve and keyed thereto for rotation therewith for engagthe movableclamping members to move the same toward the normally stationaryclamping members against the action of the springs, a second collaradjustably secured to each sleeve, a spring located between each saidsecond collar and its associated cam for permitting movement of the camsaway from their respective normally stationary clamping members in theevent that movement of the movable clamping members toward theirrespective normally stationary clamping members is impeded, means foradjustably positioning the sleeves and the elements carried therebyalong the shaft and for securing the normally stationary clampingmembers in adjusted position to the supporting base and for holding thenormally stationary clamping members against rotation with the shaft andsleeves, means for holding the movable clamping mem bers againstrotation with the shaft and sleeves, means including a relay, a firstcam operated switch operated by the shaft for energizing the relay anda, second cam operated switch operated by the shaft for deenergizing therelay to apply electrical energy to the two pairs of clamping membersonly when the coil spring is clamped thereby, one of said cam operatedswitches being adjustable to regulate the time interval during which therelay is energized and electrical energy is applied to the two pairs ofclamping members.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,105,105 Zimmerman Jan. 11, 1938 2,116,327 Simmons May 3,1938 2,124,329 Zimmerman l July 19, 1938 2,254,525 Hathaway et a1 Sept.2, 1941 2,261,878 Hathaway Nov. 4, 1941 2,443,386 Waldie June 15, 19482,574,606 Willenborg Nov. 13, 1951

